Improvement of Fabry Disease-Related Gastrointestinal Symptoms in a Significant Proportion of Female Patients Treated with Agalsidase Beta: Data from the Fabry Registry

Effects of Current Therapies on Disease Progression in Fabry Disease: A Narrative Review for Better Patient Management in Clinical Practice

Fabry disease (FD) is a rare lysosomal storage disorder that is characterized by renal, neurological, and cardiovascular dysfunction. Four treatments are currently available for patients with FD; three enzyme replacement therapies (ERTs; agalsidase alfa, agalsidase beta, and pegunigalsidase alfa) and one pharmacological chaperone (migalastat). This review focuses on the evidence for the benefits of ERTs and migalastat, and provides an overview of their impact on disease manifestations and quality of life (QoL). Agalsidase beta is associated with renal, neurological, and cardiovascular benefits, and may prevent renal disease progression. Agalsidase alfa provides stabilizing effects across all main organ systems, although minor sex-specific differences exist in patients with more advanced baseline disease. The benefits of agalsidase alfa and agalsidase beta are similar but depend on the extent of baseline disease. Some data indicate that agalsidase beta may be preferable over the longer term. Both agalsidase alfa and agalsidase beta are associated with improved gastrointestinal and pain symptoms, as well as improved QoL. Patients with advanced end-organ damage tend not to respond as optimally to ERTs as those who initiate ERTs before irreversible organ fibrosis develops, highlighting the need for early treatment initiation. Migalastat, which is only approved for patients with amenable missense gene variants, generally stabilizes renal parameters and provides cardiovascular benefits. Migalastat also improves diarrhea and pain, and stabilizes QoL (although ERT may be more effective for pain management), but the neurological effects of migalastat have not been studied. Real-world data raise concerns about effective in vivo amenability of some genetic variants. Future studies with direct treatment comparisons in patients with FD are needed.

Characterization of Fabry disease-associated lyso-Gb3 on mouse colonic ion transport and motility

Fabry disease (FD) is a rare X-linked lysosomal storage disorder caused by a deficiency in α-galactosidase A leading to the accumulation of globotriaosylceramide (Gb3) and subsequent increase in globotriaosylsphingosine (lyso-Gb3) in different cells and organs, including the gastrointestinal (GI) tract. GI symptoms represent some of the earliest manifestations of FD and significantly impact quality of life. The origin of these symptoms is complex, and the exact mechanisms remain poorly understood. Here, we sought to determine whether lyso-Gb3 contributes to the pathophysiology of GI symptoms associated with FD by examining its effects on mouse colonic ion transport and motility ex vivo using Ussing chambers and organ baths, respectively. Lyso-Gb3 significantly increased colonic baseline short-circuit current (Isc). This increase in Isc was insensitive to inhibition of the cystic fibrosis transmembrane conductance regulator and Na-K-Cl cotransporter 1, suggesting that the increase in Isc is Cl- ion independent. This response was also insensitive to inhibition by the neurotoxin, tetrodotoxin. In addition, pretreatment with lyso-Gb3 did not significantly influence subsequent responses to either veratridine or capsaicin implying that the response to lyso-Gb3 does not involve the enteric nervous system. In terms of colonic motility, lyso-Gb3 did not significantly influence colonic tone, spontaneous contractility, or cholinergic-induced contractions. These data suggest that lyso-Gb3 significantly influences ion transport in mouse colon, but that accumulation of Gb3 may be a prerequisite for the more pronounced disturbances in GI physiology characteristic of FD.NEW & NOTEWORTHY Fabry disease-associated lyso-Gb3 significantly influences mouse colonic ion transport in a Cl- ion-independent manner.

Disruption of the microbiota-gut-brain axis is a defining characteristic of the α-Gal A (-/0) mouse model of Fabry disease

Fabry disease (FD) is an X-linked metabolic disease caused by a deficiency in α-galactosidase A (α-Gal A) activity. This causes accumulation of glycosphingolipids, especially globotriaosylceramide (Gb3), in different cells and organs. Neuropathic pain and gastrointestinal (GI) symptoms, such as abdominal pain, nausea, diarrhea, constipation, and early satiety, are the most frequent symptoms reported by FD patients and severely affect their quality of life. It is generally accepted that Gb3 and lyso-Gb3 are involved in the symptoms; nevertheless, the origin of these symptoms is complex and multifactorial, and the exact mechanisms of pathogenesis are still poorly understood. Here, we used a murine model of FD, the male α-Gal A (-/0) mouse, to characterize functionality, behavior, and microbiota in an attempt to elucidate the microbiota-gut-brain axis at three different ages. We provided evidence of a diarrhea-like phenotype and visceral hypersensitivity in our FD model together with reduced locomotor activity and anxiety-like behavior. We also showed for the first time that symptomology was associated with early compositional and functional dysbiosis of the gut microbiota, paralleled by alterations in fecal short-chain fatty acid levels, which partly persisted with advancing age. Interestingly, most of the dysbiotic features suggested a disruption of gut homeostasis, possibly contributing to accelerated intestinal transit, visceral hypersensitivity, and impaired communication along the gut-brain axis.

Global reach of over 20 years of experience in the patient-centered Fabry Registry: Advancement of Fabry disease expertise and dissemination of real-world evidence to the Fabry community

Fabry disease (FD, α-galactosidase A deficiency) is a rare, progressive, complex lysosomal storage disorder affecting multiple organ systems with a diverse spectrum of clinical phenotypes, particularly among female patients. Knowledge of its clinical course was still limited in 2001 when FD-specific therapies first became available and the Fabry Registry (NCT00196742; sponsor: Sanofi) was initiated as a global observational study. The Fabry Registry has now been operational for over 20 years, overseen by expert Boards of Advisors, and has collected real-world demographic and longitudinal clinical data from more than 8000 individuals with FD. Leveraging the accumulating evidence base, multidisciplinary collaborations have resulted in the creation of 32 peer-reviewed scientific publications, which have contributed to the greatly expanded knowledge on the onset and progression of FD, its clinical management, the role of sex and genetics, the outcomes of enzyme replacement therapy with agalsidase beta, and prognostic factors. We review how the Fabry Registry has evolved from its inception to become the largest global source of real-world FD patient data, and how the generated scientific evidence has helped to better inform the medical community, individuals living with FD, patient organizations, and other stakeholders. The patient-centered Fabry Registry fosters collaborative research partnerships with the overarching goal of optimizing the clinical management of patients with FD and is well positioned to add to its past achievements.

Gut dysmotility in children with neurological impairment: the nutritional management

Intestinal motility disorders represent a frequent problem in children with neurological impairment. These conditions are characterized by abnormal movements of the gut, which can result in symptoms such as constipation, diarrhea, reflux, and vomiting. The underlying mechanisms leading to dysmotility are various, and the clinical manifestations are often nonspecific. Nutritional management is an important aspect of care for children with gut dysmotility, as it can help to improve their quality of life. Oral feeding, when safe and in the absence of risk of ingestion or severe dysphagia, should always be encouraged. When oral nutrition is insufficient or potentially harmful, it is necessary to switch to an enteral by tube or parenteral nutrition before the onset of malnutrition. In most cases, children with severe gut dysmotility may require feeding via a permanent gastrostomy tube to ensure adequate nutrition and hydration. Drugs may be necessary to help manage gut dysmotility, such as laxatives, anticholinergics and prokinetic agents. Nutritional management of patients with neurological impairment often requires an individualized care plan to optimize growth and nutrition and to improve overall health outcomes. This review tries to sum up most significant neurogenetic and neurometabolic disorders associated with gut dysmotility that may require a specific multidisciplinary care, identifying a proposal of nutritional and medical management.

Clinical relevance of globotriaosylceramide accumulation in Fabry disease and the effect of agalsidase beta in affected tissues

Fabry disease (FD) is a rare lysosomal storage disorder, characterized by a reduction in α-galactosidase A enzyme activity and the progressive accumulation of globotriaosylceramide (GL3) and its metabolites in the cells of various organs. Agalsidase beta, an enzyme replacement therapy (ERT), is approved for use in patients with FD in Europe, Canada, Australia, South America, and Asia, and is the only ERT approved for use in the United States. In this review, we discuss the clinical relevance of GL3 accumulation, the effect of agalsidase beta on GL3 in target tissues, and the association between treatment-related tissue GL3 clearance and long-term structure, function, or clinical outcomes. Accumulation of GL3 in the kidney, heart, vasculature, neurons, skin, gastrointestinal tract and auditory system correlates to cellular damage and irreversible organ damage, as a result of sclerosis, fibrosis, apoptosis, inflammation, and endothelial dysfunction. Damage leads to renal dysfunction and end-stage renal disease; myocardial hypertrophy with heart failure and arrhythmias; ischemic stroke; neuropathic pain; skin lesions; intestinal ischemia and dysmotility; and hearing loss. Treatment with agalsidase beta is effective in substantially clearing GL3 in a range of cells from the tissues affected by FD. Agalsidase beta has also been shown to slow renal decline and lower the overall risk of clinical progression, demonstrating an indirect link between treatment-related GL3 clearance and stabilization of FD.

An expert consensus on practical clinical recommendations and guidance for patients with classic Fabry disease

Fabry disease is an X-linked inherited lysosomal disorder that causes accumulation of glycosphingolipids in body fluids and tissues, leading to progressive organ damage and reduced life expectancy. It can affect both males and females and can be classified into classic or later-onset phenotypes. In classic Fabry disease, α-galactosidase A (α-Gal A) activity is absent or severely reduced and disease manifestations have an early onset that can affect multiple organs. In contrast, in later-onset Fabry disease, patients have residual α-Gal A activity and clinical features are primarily confined to the heart. Individualized therapeutic goals in Fabry disease are required due to varying phenotypes and patient characteristics, and the wide spectrum of disease severity. An international group of expert physicians convened to discuss and develop practical clinical recommendations for disease- and organ-specific therapeutic goals in Fabry disease, based on expert consensus and evidence identified through a structured literature review. Biomarkers reflecting involvement of various organs in adult patients with classic Fabry disease are discussed and consensus recommendations for disease- and organ-specific therapeutic goals are provided. These consensus recommendations should support the establishment of individualized approaches to the management of patients with classic Fabry disease by considering identification, diagnosis, and initiation of disease-specific therapies before significant organ involvement, as well as routine monitoring, to reduce morbidity, optimize patient care, and improve patient health-related quality of life.

Fabry disease - a multisystemic disease with gastrointestinal manifestations

Nonspecific gastrointestinal (GI) symptoms, such as postprandial cramping pain, diarrhea, nausea and vomiting are typical symptoms for irritable bowel syndrome or inflammatory bowel disease, but may also be the first symptoms of Fabry disease (FD). This review focus on GI manifestations in FD, by providing an overview of symptoms, a proper diagnosis, an appropriate management by FD-specific and concomitant medications and lifestyle interventions. We provide comprehensive literature-based data combined with personal experience in the management of FD patients. Since FD is rare and the clinical phenotype is heterogeneous, affected patients are often misdiagnosed. Consequently, physicians should consider FD as a possible differential diagnosis when assessing unspecific GI symptoms. Improved diagnostic tools, such as a modified GI symptom assessment scale can facilitate the diagnosis of FD in patients with GI symptoms of unknown cause and thus enable the timely initiation of a disease-specific therapy. Expansive intravenous enzyme replacement therapy with α-galactosidase A or oral chaperone therapy for patients with amenable mutations improve the disease burden including GI symptoms, but a timely start of therapy is crucial for the prognosis. A special diet low in fermentable oligosaccharides, disaccharides, monosaccharides and polyols (FODMAP) or pro- and prebiotics might improve FD-typical GI symptoms. Furthermore, preliminary success was reported with the oral administration of α-galactosidase A. In addition to a timely initiation of FD-specific therapy, affected patients with GI symptoms might benefit from a FODMAP-low diet, pro- and prebiotics and/or low-cost oral substitution with AGAL to support digestion and reduce dysbiosis.

Treatment of Anderson-Fabry Disease

Fabry disease is an X-linked disorder of glycosphingolipid metabolism that results in progressive accumulation of neutral glycosphingolipids, predominantly globotriaosylsphingosine (Gb3) in lysosomes, as well as other cellular compartments of several tissues, causing multi-organ manifestations (acroparesthesias, hypohidrosis, angiokeratomas, signs and symptoms of cardiac, renal, cerebrovascular involvement). Pathogenic mutations lead to a deficiency of the lysosomal enzyme alpha-galactosidase A (GLA). In the presence of high clinical suspicion, a careful physical examination and specific laboratory tests are required. Finally, the diagnosis of Fabry's disease is confirmed by the demonstration of the absence of or reduced alpha-galactosidase A enzyme activity in hemizygous men and gene typing in heterozygous females. Measurement of the biomarkers Gb3 and Lyso Gb3 in biological specimens may facilitate diagnosis. The current treatment of Anderson-Fabry disease is represented by enzyme replacement therapy (ERT) and oral pharmacological chaperone. Future treatments are based on new strategic approaches such as stem cell-based therapy, pharmacological approaches chaperones, mRNA therapy, and viral gene therapy. This review outlines the current therapeutic approaches and emerging treatment strategies for Anderson-Fabry disease.

Gastrointestinal Involvement in Anderson-Fabry Disease: A Narrative Review

Anderson-Fabry disease (FD) is an X-linked lysosomal storage disorder leading to a wide array of clinical manifestations. Among these, gastrointestinal (GI) symptoms such as abdominal pain, bloating, and diarrhea affect about half of the FD adults and more than half of FD children. GI symptoms could be the first manifestation of FD; however, being non-specific, they overlap with the clinical picture of other conditions, such as irritable bowel syndrome and inflammatory bowel disease. This common overlap is the main reason why FD patients are often unrecognized and diagnosis is delayed for many years. The present narrative review is aimed to promote awareness of the GI manifestations of FD amongst general practitioners and specialists and highlight the latest findings of this rare condition including diagnostic tools and therapies. Finally, we will discuss some preliminary data on a patient presenting with GI symptoms who turned to be affected by a variant of uncertain significance of alpha-galactosidase (GLA) gene.

Variable clinical features of patients with Fabry disease and outcome of enzyme replacement therapy

Fabry disease (FD) is an X-linked lysosomal storage disorder caused by a deficiency in the enzyme α-galactosidase A due to mutations in the GLA gene. This leads to an accumulation of globotriaosylceramide (GL-3) in many tissues, which results in progressive damage to the kidneys, heart, and nervous system. We present the molecular and clinical characteristics and long-term outcomes of FD patients from a multidisciplinary clinic at the University of California, Irvine treated with agalsidase beta enzyme replacement therapy (ERT) for 2-20 years. This cohort comprised 24 adults (11 males, 13 females) and two male children (median age 45; range 10-68 years). Of the 26 patients in this cohort, 20 were on ERT (12 males, 8 females). We describe one novel variant not previously reported in the literature in a patient with features of 'classic' FD. The vast majority of patients in this cohort presented with symptoms of 'classic' FD including peripheral neuropathic pain, some form of cardiac involvement, angiokeratomas, corneal verticillata, hypohidrosis, tinnitus, and gastrointestinal symptoms, primarily abdominal pain. The majority of males had clinically evident renal involvement. An annual eGFR reduction of -1.88 mL/min/1.73 m2/yr during the course of ERT was seen in this cohort. The most common renal presentation was proteinuria, and one individual required a renal transplant. Other common findings were pulmonary involvement, lymphedema, hearing loss, and significantly, three patients had strokes. Notably, there was a high prevalence of endocrine dysfunction and low bone mineral density, including several with osteoporosis. While enzyme replacement therapy (ERT) cleared plasma GL-3 in this cohort, there was limited improvement in renal function or health-related quality of life based on the patient-reported SF-36 Health Survey. Physical functioning significantly declined over the course of ERT treatment, which may be, in part, due to the late initiation of ERT in several patients. Further delineation of the phenotypic and genotypic spectrum in patients with FD and the long-term outcome of ERT will help improve management and treatment options for this disease.

FABry Disease Patient-Reported Outcome-GastroIntestinal (FABPRO-GI): A new Fabry disease-specific gastrointestinal outcomes instrument

PURPOSE

Fabry disease is a rare multisystemic disorder caused by functional deficiency of the lysosomal enzyme alpha-galactosidase A. Gastrointestinal (GI) signs and symptoms are among the earliest clinical manifestations in patients with Fabry disease but are often nonspecific, misdiagnosed, and untreated. No instruments have been developed specifically to assess GI signs and symptoms in Fabry disease. The FABry disease Patient-Reported Outcome-GastroIntestinal (FABPRO-GI) was developed to address this unmet need and is intended for use in clinical trials (24-h FABPRO-GI) and real-world settings (7-day FABPRO-GI).

METHODS

Findings from a literature review, expert advisory meetings, and patient concept elicitation interviews (CEIs) were summarized into conceptual models. These conceptual models were used to develop preliminary versions of the 24-h and 7-day FABPRO-GI. Cognitive debriefing interviews (CDIs) were conducted with additional patients to assess content validity, including understandability, relevance, and comprehensiveness of the preliminary versions of the 24-h and 7-day FABPRO-GI.

RESULTS

Literature review (n = 17 articles), expert advisory meetings (n = 5), and patient CEIs (n = 17) identified mostly overlapping Fabry disease-related GI signs and symptoms, including abdominal cramps, bloating, and diarrhea, and informed development of the preliminary 24-h and 7-day FABPRO-GI. CDIs (n = 15) provided evidence of content validity and informed revisions of the 24-h and 7-day FABPRO-GI.

CONCLUSION

With evidence of content validity, the 24-h and 7-day FABPRO-GI are the first Fabry disease-specific patient-reported outcomes to assess GI signs and symptoms in patients with Fabry disease with potential for use in clinical trials and real-world settings, respectively.

Improvement of gastrointestinal symptoms in a significant proportion of male patients with classic Fabry disease treated with agalsidase beta: A Fabry Registry analysis stratified by phenotype

Background

Fabry disease is an inherited disorder of glycolipid metabolism with progressive involvement of multiple organs, including the gastrointestinal tract, in classically affected male patients. Clinical presentations in males with later-onset Fabry phenotypes are more heterogeneous and largely dependent on the level of residual α-galactosidase A activity.

Methods

We assessed agalsidase beta treatment outcomes of gastrointestinal symptoms in adult males with classic or later-onset Fabry disease. Self-reports of abdominal pain and diarrhea ('present'/'not present' since previous assessment) at last clinical visit (≥0.5 year of follow-up) were compared with treatment-baseline.

Results

Classic male patients were considerably younger at first treatment than the fewer males with later-onset phenotypes (36 vs. ~47 years) and reported gastrointestinal symptoms more frequently at baseline (abdominal pain: 56% vs. 13%; diarrhea: 57% vs. 23%). As compared with baseline, significantly fewer classic patients reported abdominal pain after a median of 4.7 years of treatment (N = 171, 56% vs. 41%, P < 0.001). Moreover, significantly fewer patients reported diarrhea after 5.5 years of follow-up (N = 169, 57% vs. 47%, P < 0.05). Among the males with later-onset phenotypes, albeit statistically non-significant, abdominal pain reports reduced after a median of 4.2 years (N = 48, 13% vs. 4%) and diarrhea reports reduced after a median of 4.4 years of treatment (N = 47, 23% vs. 13%).

Conclusions

Sustained treatment with agalsidase beta was associated with improvement in abdominal pain and diarrhea in a significant proportion of classic male Fabry patients. Males with later-onset phenotypes reported gastrointestinal symptoms much less frequently at baseline as compared with classic patients, and non-significant reductions were observed.

The clinical profiles of female patients with Fabry disease in Latin America: A Fabry Registry analysis of natural history data from 169 patients based on enzyme replacement therapy status

BACKGROUND

Fabry disease is an X-linked lysosomal storage disorder with heterogeneous clinical expression in female patients ranging from asymptomatic to severe clinical presentations as in classic males. We assessed clinical profiles and compared natural history data of female patients eventually initiated on enzyme replacement therapy ("ERT-recipients") with those remaining untreated ("ERT-naïve").

METHODS

We analyzed Fabry Registry data from 93 ERT-recipients, collected prior to ERT initiation, and 76 ERT-naïve females with classic or unclassified phenotypes from four Latin American countries and evaluated Fabry symptoms, interventricular septum thickness, left ventricular posterior wall thickness, estimated glomerular filtration rate, and severe clinical events.

RESULTS

For 169 patients with available data, median age of first Fabry symptom manifestation was 12.7 years with peripheral pain as predominant first symptom, and diagnostic delay of 10.3 years from the first reported symptom. Female patients had high symptomatic burden during natural history follow-up, with 83% reporting peripheral pain, 69%-79% cold/heat intolerance or abnormal sweating, and 32% gastrointestinal symptoms. ERT-recipients reported similar age at first symptom as ERT-naïve patients but they were older at diagnosis (median 39.2 vs 24.4 years, P < .01) and last follow-up (median 43.4 vs 28.2 years, P < .01). Reported Fabry symptom frequencies and abnormal echocardiography findings were higher in ERT-recipients. Functional renal assessments were normal and similar.

CONCLUSIONS

Female patients from Latin America have notable diagnostic delays and high symptomatic burden. ERT was prescribed late in females with advanced age at diagnosis and advanced disease. There remained many female patients who had been diagnosed at younger age, had substantial Fabry manifestations, but did not receive disease-specific treatment.

Lyso-Gb3 modulates the gut microbiota and decreases butyrate production

Fabry disease is a rare X-linked lysosomal storage disorder resulting from deficient activity of α-galactosidase A, leading to the accumulation of glycosphingolipids such as globotriaosylsphingosine (lyso-Gb3). The gastrointestinal symptoms of this disease may be disabling, and the life expectancy of affected patients is shortened by kidney and heart disease. Our hypothesis was that lyso-Gb3 may modify the gut microbiota. The impact of a clinically relevant concentration of lyso-Gb3 on mono- or multispecies bacterial biofilms were evaluated. A complex bacterial community from the simulated transverse colon microbiota was studied using quantitative PCR to estimate different bacterial group concentrations and a HPLC was used to estimate short-chain fatty acids concentrations. We found that lyso-Gb3 increased the biofilm-forming capacity of several individual bacteria, including Bacteroides fragilis and significantly increased the growth of B. fragilis in a multispecies biofilm. Lyso-Gb3 also modified the bacterial composition of the human colon microbiota suspension, increasing bacterial counts of B. fragilis, among others. Finally, lyso-Gb3 modified the formation of short-chain fatty acids, leading to a striking decrease in butyrate concentration. Lyso-Gb3 modifies the biology of gut bacteria, favoring the production of biofilms and altering the composition and short-chain fatty-acid profile of the gut microbiota.

The effect of enzyme replacement therapy on clinical outcomes in female patients with Fabry disease - A systematic literature review by a European panel of experts

BACKGROUND

Heterozygous females with Fabry disease have a wide range of clinical phenotypes depending on the nature of their mutation and their X-chromosome inactivation pattern; it is therefore important to examine outcomes of enzyme replacement therapy (ERT) in the female patient population specifically. This paper presents the findings of a systematic literature review of treatment outcomes with ERT in adult female patients.

METHODS

A comprehensive systematic literature review was conducted through January 2017 to retrieve published papers with original data on ERT in the treatment of Fabry disease. The review included all original articles that presented ERT outcomes data on patients with Fabry disease, irrespective of the study type.

RESULTS

Clinical evidence for the efficacy of ERT in female patients was available from 67 publications including six clinical trial publications, and indicates significant reductions in plasma and urine globotriaosylceramide (GL-3) accumulation (in female patients with elevated pre-treatment levels) and improvements in cardiac parameters and quality of life (QoL). To date, data are insufficient to conclude on the effects of ERT on the nervous system, gastrointestinal manifestations, and pain in female patients with Fabry disease.

CONCLUSIONS

This review of available literature data demonstrates that ERT in adult female patients with Fabry disease has a beneficial effect on GL-3 levels and cardiac outcomes. The current evidence also suggests that ERT may improve QoL in this patient population, though further studies are needed to examine these results.

European expert consensus statement on therapeutic goals in Fabry disease

BACKGROUND

Fabry disease, an inherited lysosomal storage disorder, causes multi-organ pathology resulting in substantial morbidity and a reduced life expectancy. Although Fabry disease is an X-linked disorder, both genders may be affected, but generally to a lesser extent in females. The disease spectrum ranges from classic early-onset disease to non-classic later-onset phenotypes, with complications occurring in multiple organs or being confined to a single organ system depending on the stage of the disease. The impact of therapy depends upon patient- and disease-specific factors and timing of initiation.

METHODS

A European panel of experts collaborated to develop a set of organ-specific therapeutic goals for Fabry disease, based on evidence identified in a recent systematic literature review and consensus opinion.

RESULTS

A series of organ-specific treatment goals were developed. For each organ system, optimal treatment strategies accounted for inter-patient differences in disease severity, natural history, and treatment responses as well as the negative burden of therapy and the importance of multidisciplinary care. The consensus therapeutic goals and proposed patient management algorithm take into account the need for early disease-specific therapy to delay or slow the progression of disease as well as non-specific adjunctive therapies that prevent or treat the effects of organ damage on quality of life and long-term prognosis.

CONCLUSIONS

These consensus recommendations help advance Fabry disease management by considering the balance between anticipated clinical benefits and potential therapy-related challenges in order to facilitate individualized treatment, optimize patient care and improve quality of life.

Non-specific gastrointestinal features: Could it be Fabry disease?

Non-specific gastrointestinal symptoms, including pain, diarrhoea, nausea, and vomiting, can be the first symptoms of Fabry disease. They may suggest more common disorders, e.g. irritable bowel syndrome or inflammatory bowel disease. The confounding clinical presentation and rarity of Fabry disease often cause long diagnostic delays and multiple misdiagnoses. Therefore, specialists involved in the clinical evaluation of non-specific upper and lower gastrointestinal symptoms should recognize Fabry disease as a possible cause of the symptoms, and should consider Fabry disease as a possible differential diagnosis. When symptoms or family history suggest Fabry disease, in men, low alpha-galactosidase A enzyme levels, and in women, specific Fabry mutations confirm the diagnosis. In addition to symptomatic treatments, disease-specific enzyme replacement therapy with recombinant human alpha-galactosidase A enzyme or chaperone therapy (migalastat) in patients with amenable mutations can improve the disease, including gastrointestinal symptoms, and should be initiated as early as possible after Fabry disease has been confirmed; starting enzyme replacement therapy at as young an age as possible after diagnosis improves long-term clinical outcomes. Improved diagnostic tools, such as a modified gastrointestinal symptom rating scale, may facilitate diagnosing Fabry disease in patients with gastrointestinal symptoms of unknown cause and thus assure timely initiation of disease-specific treatment.